The preparation and processing of synthetic fibers and filaments require the use of auxiliary synthetic fiber agents. Their function is to provide the fibers and filaments with the properties necessary for their preparation and further processing, such as for example, smoothness, anti-static properties, fiber adhesion, etc. Since the requirements concerning auxiliary chemical agents for fibers are highly varied, normally the use of a single chemical substance is not sufficient and special mixtures must be applied. Quantitatively, the largest proportion normally consists of lubricants.
In the past, usually mineral oils of various compositions and viscosities or ester oils of different chemical structures, or mixtures of both, were applied as lubricants. Their principal advantage resides in the fact that they are capable of providing the synthetic fibers with any desired or required smoothness, when used in correct proportions. Viscosity is a highly important criterion of selection for this purpose. In general, the lower the viscosity, the lower the friction between the fiber and a friction body. Due to their low boiling points or boiling ranges, they exhibit the disadvantages of high volatility, poor adhesion to fibers and low heat resistance. Because of the high volatility and poor fiber adhesion, the fiber is partially deprived of the protective action of the spin preparation. This may lead to mechanically caused damage, and furthermore, deposits are formed in or on the heated parts of the processing machinery, for example, on heated harnesses, heating plates and hot pins of draw frames or draw-twisters or in the convection or contact heaters of texturing machines, etc. Because of their low heat resistance, these deposits are decomposed easily and rapidly. The liquid or tar-like or solid decomposition products are capable of strongly hindering the manufacturing process or even of rendering it inoperable. Less volatile, heat resistant products normally have higher viscosities and thus have higher friction coefficients, which makes them unsuitable as lubricants.
The above is true, with certain qualifications, for the other components of spinning preparations.
In the past, when relatively low processing velocities and lower processing temperatures were used, these problems were not as severe, and means were found to handle them. In spite of this, as early as in the 1960's, the need for less volatile and heat resistant preparations became apparent.
The very rapid technical progress of the last 10 years with the development of rapid spinning and stretch-spinning processes for filaments and staple fibers, of stretch-spinning texturing processes, of BCF yarns (bulked continuous filaments) and stretch texturing processes of filaments at very high velocities, rendered the development of entirely new preparations necessary. The principal requirements were: heat resistance, low volatility, good anti-static effectiveness, good wetting ability, adequate fiber adhesion ability, compatibility with other auxiliary agents, such as for example, spooling oil or fats, and good washability.
These requirements made the use of new, synthetic substances necessary. Mineral oils and most of the ester oils were eliminated because of their low boiling points, the resulting volatility and their low heat resistance.
The problem therefore consisted of finding lubricants which would provide synthetic fibers and filaments with moderate or low frictional properties between fibers and a friction body and simultaneously with good fiber adhesion, while having good resistance to heat and adhesion to the fibers, so that deposits in heaters or on heating plates, harnesses, etc. are prevented or restricted to a minimum.
Ethoxylated fatty alcohols or fatty acids have been known for a long time as lubricants, which when applied to fibers, provide intermediate to low friction between fibers and friction bodies, but in general do not satisfy the requirements concerning heat resistance and volatility.
A new development consists of the group of poly(ethylene)-propylene-oxide mixed alkoxylates, which represent good lubricating components even at intermediate viscosities of the products and cause no deposits on machine parts at working temperatures around 250.degree. C., due to their depolymerization without residues at such temperatures . Mixed oxyalkylates based, for example, on butanol or pentaerythritol are known for this purpose.
U.S. Pat. No. 3,997,450 describes the use of alkyl-terminated oxyethylates as a preparation agent, for example, the methyl ether of a coconut fatty alcohol converted with ethylene oxide. In German Pat. No. 15 20 647 are described polyethers terminated by olefins, for example, the tertiary butyl ethers of alcohols. They may be obtained by means of reacting the corresponding alcohols with isobutylene. It is known from these compounds to block open alcoholic hydroxyl groups in the terminal positions.